Page 278 - Environment: The Science Behind the Stories

content after 27 years. They found that
soil carbon had decreased in all treat-
ments, but that it had declined most in
conventional plots. Conventional plots Organic Conventional
supplemented with manure, however,
did just as well as the organic plots in
retaining soil carbon.
Organic farming has proved even
more successful in Pennsylvania, where Organic Conventional
the Rodale Institute has compared
organic and conventional fields of corn
and soybeans in a large-scale experi-
ment running since 1981 on its 330-
acre farm. In 2011 it released results
from 30 years’ worth of data (Figure 2).
Averaged across the 30 years, Figure 3 organically grown corn did better than conventionally grown corn during
yields of organically grown crops periods of drought in the rodale institute experiment. Better-quality soil was part of the
equaled yields of conventionally grown reason.
crops. Moreover, the organic crops

required 30% less energy input. For life, earthworm activity, water-holding
this reason, raising them released capacity, topsoil depth, and naturally
Organic 35% fewer greenhouse gas emissions. occurring nutrients.
Conventional
5000 Because of lower energy inputs and Given such differences in soil
higher crop prices for organic produce, quality, researchers expect that organic
4000 farming organically created three times fields should perform better and better

3000 the profit for the farmer. relative to conventional fields as time
As with the Swiss experiment, the goes by — in other words, that they are
2000
secret lies in the soil. At the Rodale more sustainable. Moreover, the striking
1000 Institute’s farm over the years, the soil yield results of the Rodale experiment
of the organic fields became visibly suggest that perhaps organic agricul-
0 darker and better textured than the ture can feed the world’s people every
Energy input
Yields (lbs/acre/yr) (megajoules/acre/yr) conventional fields’ soil. This helped bit as reliably as today’s conventional
Greenhouse gases
Profit ($/acre/yr)
(lbs CO 2 /acre/yr)
corn crops in the organic fields to out-
industrial agriculture.
As more long-term data are
during times of drought (Figure 3).
Figure 2 organic crops equaled conven- perform those in the conventional fields published and new studies begin, we
tional crops in yields while producing Shorter-term experiments else- are learning more and more about the CHAPTER 10 • A g R i C ulT u RE , Bi o TECH nology, A nd THE Fu T u RE o F Food
more profit, requiring less energy input, where have shown similar results. benefits of organic agriculture for soil
and releasing fewer greenhouse gas emis- Researchers comparing organic and quality — and about how we might
sions. Data from Rodale Institute, 2011. The conventional farms in North Dakota and improve conventional methods to maxi-
farming systems trial: Celebrating 30 years. Rodale Nebraska have found that organic farm- mize crop yields while protecting the
Institute, Kutztown, Pennsylvania. ing produces soils with more microbial long-term sustainability of agriculture.

soil quality and encourages pollinating insects. Surveys reveal Many consumers favor organic food out of concern about
that farmers who adopt organic techniques do so primarily health risks posed by the pesticides, hormones, and antibiotics
because they want to practice stewardship toward the land and used in conventional agriculture. Consumers also buy organic
to safeguard their family’s health. Farmers face obstacles to products out of a desire to improve environmental quality. The
adopting organic methods, however. Foremost among these main obstacle for consumers is price. Organic products tend to
are the risks and costs of shifting to new methods, particularly be 10–30% more expensive than conventional ones, and some
during the transition period. For instance, U.S. farmers need (such as milk) can cost twice as much. However, enough con-
to meet standards for three years before their products can be sumers are willing to pay more for organic products that grocers
certified. and other businesses are making them more widely available. 277

M10_WITH7428_05_SE_C10.indd 277 12/12/14 2:59 PM